Abstract: At 9:30 a.m. on July 18, 2017, Employee #1 and Coworker #1, employed by a mechanical contractor, were working at a multiemployer construction project, a water treatment facility. They were on top of the Clarifier/Flocculation Basin and pushing stems through two open hatches. As Coworker #1 pushed the stems into the guides, Employee #1 peered into one of the open hatches to help line up the stems. Coworker #1 requested cribbing to hold up the stems. As Employee #1 turned to go for the needed material, he stepped into and fell through the open hatch to the concrete surface below, a fall height of approximately 22.5 feet. Emergency services were called, and Employee #1 was transported to the hospital. He was admitted and treated for fractured ribs, a punctured lung, a fractured shoulder blade, crushed vertebrae, and a ruptured back disc.